Water Resources Test - 1

The Spiti area of Himachal Pradesh is a cold desert which is snowbound for half a year. Rainfall is negligible and the soil is dry and lacks organic matter. Farmers have developed a specific irrigation system using kuls (diversion channels) to carry water from glaciers to the villages. The kuls often span long distances, running down precipitous mountain slopes and across crags and crevices. Some kuls are 10 km long, and have existed for centuries. The crucial portion of a kul is its head at the glacier, which is to be tapped. The head must be kept free of debris, and so the kul is lined with stones to prevent clogging and seepage. In the village, the kul leads to a circular tank from which the flow of water can be regulated. For example, when there is need to irrigate, water is let out of the tank in a trickle. Water from the kul is collected through the night and released into the exit channel in the morning. By evening, the tank is practically empty, and the exit is closed. Khadins and Johads are the rain fed storage structures that allow water to stand and moisten the soil in Rajasthan. They are rain fed storage structures that allow water to stand and moisten the soil in Rajasthan.

The Palar Pani is a term referred to the rainwater in the desert regions of Rajasthan, which is regarded as the purified form of natural water. This water in the region is perceived value and thus the conservation of this water takes place underground. People of Rajasthan usually consume this water during the summer season when all the reservoirs dry. In the semi-arid and arid regions of Rajasthan, particularly in Bikaner, Phalodi and Barmer, almost all the houses traditionally had underground tanks or tankas for storing drinking water.

People in Rajasthan follow rooftop water harvesting to store drinking water. In the arid and semi-arid regions, the agricultural fields are covered in water storage structures which store rainwater. This allows the soil to be moistened, like we see "khadins" in Jaisalmer and "johads" in the other parts of Rajasthan. In the semi-arid and arid regions, particularly in Bikaner, Phalodi and Barmer, most of the houses have traditional underground water storage tanks or "tankas" for the storage of drinking water. The sizes of the tanks differ; they can be a big room size inside the main house or a storage tank in the courtyard. They are connected to the sloping roofs of the houses through a pipe. The rainwater falls down the pipes and is collected in the underground "tankas".

Tamil Nadu is the first state in India which has made rooftop rainwater harvesting structure compulsory to all the houses across the state. There are legal provisions to punish the defaulters. The harvesting of rainwater simply involves the collection of water from surfaces on which rain falls, and subsequently storing this water for later use. The practice has been patchy in many parts of the country, but Tamil Nadu's experiment with the alternative water conservation technique is a rare success story.The Rain Water Harvesting (RWH) scheme, Tamil Nadu chief minister J Jayalalithaa, was launched in 2001 in a bid to rejuvenate water sources and improve ground water levels in the parched southern state.

In semi-arid regions of Rajasthan every house had underground tankas to store the water for drinking purposes. These tankas are large and deep tanks which were built inside the main house or the courtyard. They were linked to the sloping roofs of the houses through a pipe. Rainwater falling on the rooftops would run down through the pipe and collect in the underground tankas. The rainwater collected was stored in the underground tankas providing drinking water till the next seasons. When all other sources have dried up, these tankas are beneficial to beat the summer heat as they keep the rooms cool.

Bhopal lake was the largest artificial lake built in the eleventh century. Bhojtal (Bhopal lake), formerly known as Upper Lake, and Shah Ali Shah Talaab, is a large lake which lies on the western side of the capital city of Madhya Pradesh, Bhopal. It is a major source of drinking water for the residents of the city, serving around 40% of the residents with nearly 30 million imperial gallons (140,000 m³) of water per day. Bada Taalab, along with the nearby Chhota Talaab, meaning small lake in Hindi, constitutes Bhoj Wetland, which is now a Ramsar site.

About 70 percent of the earth is water, but only 2.5 percent of that is freshwater. Of the freshwater, 68.9 percent is in the form of glaciers and snow cover, 30.8 percent is groundwater, and about 0.3 percent is in lakes and rivers.

Groundwater depletion, a term often defined as long-term water-level declines caused by sustained groundwater pumping, is a key issue associated with groundwater use. Pumping motors in urban households, colonies, etc. suck up the ground water and cause depletion of water table.
Some of the negative effects of groundwater depletion:
Drying up of wells
Reduction of water in streams and lakes
Deterioration of water quality
Increased pumping costs
Land subsidence

Jawaharlal Nehru proudly proclaimed the dams as the 'temples of modern India' as it was felt that the construction of large dams would solve many problems of India. It would result in the generation of electricity, would provide water for irrigation to the farmers, supply water to household and industries.

In the arid and semi-arid regions, agricultural fields were converted into rain fed storage structures that allowed the water to sand and moisten the soil; these water storage structures are known as Khadins in Jaisalmer.

A dam is a barrier across flowing water that obstructs, directs or retards the flow, often creating a reservoir, lake or impoundment. Dams are built for irrigation, electricity generation, water supply for domestic and industrial uses, flood control, recreation, inland navigation and fish breeding. A dam failure or dam burst is a catastrophic type of failure characterised by the sudden, rapid, and uncontrolled release of impounded water or the likelihood of such an uncontrolled release. Between the years 2000 and 2009, more than 200 notable dam failures happened worldwide. Dams help in conserving and managing water by storing large amount of water so that when there is no rain and your crops are too dry, you can get water from the dam and it gets water from the river and rain.

At Sringaverapura near Allahabad in Uttar Pradesh, India, there exists an extraordinary example of hydraulic engineering dating back to the end of the 1st century BC. It comprises three percolation-cum-storage tanks, fed by an 11 m wide and 5 m deep canal that used to skim the floodwaters off the monsoon-swollen Ganga.

According to Falken Mark, a Swedish expert, water stress occurs when water availability is less than 1,000 cubic metre per person per day. Malin Fredrika Sofia Sundberg-Falkenmark, born 21 November 1925 in Stockholm, is a Swedish hydrologist. Falkenmark is best known for her long-standing work and expertise on the sustainable use of water resources to meet human and ecosystem needs.

In the arid and semi-arid regions, agricultural fields were converted into rain fed storage structures that allowed the water to sand and moisten the soil; these water storage structures are known as Khadins in Jaisalmer (Rajasthan) and Johads in other parts of Rajasthan.

Floodwater enters the fields through the inundation canals, carrying not only rich silt but also fishes, which swim through these canals into the lakes and tanks to feed on the larva of mosquitoes. This helps to check malaria in the region. According to Willcocks, the ancient system of overflow irrigation had lasted for thousands of years. The bamboo drip irrigation system is normally used to irrigate the betel leaf or black pepper crops planted in areca nut orchards or in mixed orchards. Bamboo pipes are used to divert perennial springs on the hilltops to the lower reaches by gravity. The channel sections, made of bamboo, divert and convey water to the plot site where it is distributed without leakage into branches, again made and laid out with different forms of bamboo pipes.